Synthetic Study On Karst Collapse Prevention Of Important Project

When important project selected location should avoid the karst growth area as far as possible, but receives the detachment condition limit, many projects still inevitably must arrange in the karst area, the karst collapse is the main geological disaster which the engineering construction possibly suffers. The newly built Kunming international airport geological environment condition is complex, the karst growth is intense, karst collapse universally exist, The karst collapse is the most main engineering geological question which the new airport construction faces. The Kunming New Airport karst collapse has south China the karst collapse typical characteristic, take the Kunming New Airport as example development karst collapse prevention synthetic study, not only has the instruction function to the Kunming New Airport prevention and the government karst collapse, moreover also has to other karst area important project's karst collapse prevention profits from the significance. This article is in the full collection, uses the domestic and foreign karst collapse aspect in the material foundation, unifies the Kunming New Airport example development karst collapse integrated control research the achievement.(1) Has conducted the system research to the new airport's geological environment, to the new airport hydrometeorology, the terrain landform, the formation lithology, the geologic structure, the hydrology geology, the karst growth characteristic and so on has carried on the system analysis, the induction.(2) Have carried on the system analysis, the research to the new airport karst collapse's formation condition and the influencing factor. Using the MapGIS spatial analysis tool, after will be related the foundation graphic document and the karst collapse distribution map superimposition, to the karst condition of development, the cap rock condition and sends collapses in the dynamic condition 15 influencing factor to carry on the multianalysis, the research.. The project area karst growth degree has the consistent increase and decrease relations with the collapse frequency: In the D2h stratum the karst collapse most grows; Next,in the D3z stratum growth; Then, in the P1y, C2w, C1d2 stratum grows;∈2s in stratum few growth.. In a Yuan structure's red clay coating soil body the netted crevasse grows specially, easiest to form the karst collapse; In the project area loose level thickness is smaller, easier to have the karst collapse, the depth of cover is smaller than the 15m collapse accounts for the collapse total 94%. Sends collapses the dynamic condition including the mospheric water, the surface water, the ground water, the ditional load and the karst medium and the atmospheric link situation and so on major effect factor, mospheric water's function is especially prominent.(3) Divides according to the leading origin, the project area karst collapse type infiltrates including the precipitation under sends collapses, the groundwater level to drop sends collapses and moves the load to send collapses falls sends collapses three types. Under after the precipitation infiltrates the mechanism which sends collapses is the precipitation permeates the loose cap rock, the current of water to the cap rock soil body has the vertical seepage, saturated to increase heavy and the absorbing water ramollescence, causes the loose cap rock jitter under these strength's combined action until collapsing. In the project area drops the karst collapse which by the phreatic water surface sends collapses is mainly by the real suction eclipse function and the action of gravity causes; Moves the load to send collapses, is mainly the destruction accumulation effect which produces by the vibration causes. In the system analysis, in the research collapse mechanism's foundation, established under the precipitation to infiltrate separately sends collapses, the ground water to drop sends collapses under the mechanism the karst collapse stable appraisal mechanical model. In the project area the majority of karst collapse's formation is the multiple reason compound superimposition function result, causes the karst collapse by the sole reason is only minority. The project area typical karst collapse forms the pattern to have under the surface water to infiltrate and to move the load to send collapses the pattern, the ground water to drop sends collapses the pattern two kinds.(4) Uses the fuzzy level synthesis method to carry on the forecast appraisal to the project area karst collapse risk. In the system analysis main karst collapse influence factor's foundation, establishes the fuzzy level evaluation model, the determination different level different influence factor weight; Unifies the MapGIS spatial analysis tool, to includes the different weight to send respectively collapses the factor to carry on the spatial repeat to set at the analysis computation, according to the computed result determined that the karst collapse risky rank and carries on the karst collapse risky district to the project area, then carries on the district forecast appraisal. Chooses method being suitable, reliably, the forecasting result is credible.(5) Has established the new airport karst collapse database and the information system, for the new airport karst collapse's system analysis, the appraisal provided the material to be full and accurate, the method advanced management platform, caused the airport construction and the Administrative unit can carry on the convenient inquiry and the use to the karst collapse material, had the big practical significance.(6) In the full summary, induces in the domestic and foreign karst collapse prevention experience's foundation, the choice has the representative pilot area, has carried out the karst collapse prevention engineering test research. In view of karst collapse's formation condition and the influencing factor, the selection handling object and the testing method, experiments in view of the underlying limestone cave and the red clay coating carries on separately, underlying limestone cave's processing uses the concretes + sleeve valve note thick liquid law; The red clay uses the breaker strip strong hang law and the broken stone marker law carries on processing. After the experiment, uses many kinds of examination methods to carry on the examination, the confirmation. The testing method is correct, being suitable, the examination method is objective, is reliable, the control efficiency is obvious.(7)According to the project area prevention experiment achievement and the domestic and foreign karst collapse project prevention experience, proposed the project area karst collapse prevention handling object and the method suggested that the division of work energy region put forward the karst collapse prevention plan proposal separately. After will take the project prevention measure, affects the factor the improvement situation again value, then takes the office district and west the flight area carries on the computation, the forecast to the karst collapse risk, will adopt the mechanical control measure before and after result to carry on the comparison, thought that project prevention plan being suitable, feasible, the effect is quite obvious.(8)Utilize the systems science and the operations research theory in the karst collapse project prevention decision-making, and so on has conducted the exploring research to the karst collapse prevention project decision model and the method, has the vital significance regarding the geological disaster's prevention and the management. Unifies this project actual situation according to the decision-making study theory, proposed the Kunming New Airport karst collapse prevention project decision model is: Definite goal -> collection information -> determination decision-making criterion -> formulation prevention plan -> to each kind of plan policy-making criterion analysis, computation -> choice decision method -> decision-making: Choice synergy. The union project reality, chooses while the division, the effect method of correlates, the linear weighted sum law, the analytic hierarchy process carries on the policy-making computation separately, used the compound decision law to determine the office district and west the flight area prevention plan. The decision method is objective, reasonably, has provided the basis for the new airport science prevention karst collapse decision-making.The paper in the system analysis, the elaboration project area karst collapse origin, in mechanism's foundation, forms the condition and the influencing factor take the karst collapse as a center, has conducted the synthetic study to the project area karst collapse prevention and put forward the project prevention proposal. The paper achievement has achieved the anticipated target, not can only construct certain instruction function for the Kunming New Airport, moreover also has to other similar important project's karst collapse prevention profits from the significance.